Computational fluid dynamics analysis on the course stability of a towed ship

Abstract

Due to the highly complex phenomenon of a ship towing system associated with the presence of a dynamic nonlinear towline tension, a reliable investigation allowing for an accurate prediction of the towed ship's course stability is obviously required. To achieve the objective, a Computational Fluid Dynamic simulation approach is proposed by investigating attainable and precise course stability outcomes, whilst a hydrodynamic description underlying the rationale behind the results is explained. Several towing parameters such as various towline lengths and tow point locations with respect to the centre of gravity of the barge have been taken into account. Here, tug and barge is employed in the simulation as the tow and towed ship, respectively. In addition, a towing velocity is constantly applied on the tug. The results revealed that the course stability of the towed ship increases in the form of more vigorous fishtailing motions as the towline length subsequently increases from 1.0 to 3.0. Meanwhile, the increase of tow point location from 0.5 to 1.0 leads to a significant improvement in the course stability of the towed ship, as indicated by the reduction of the sway and yaw motions by 227% and 328%, respectively. It is concluded that the increase of tow point location is a recommended decision to achieve a better towing course stability for the barge.

Longitudinal motion control for high-speed trimaran based on computational fluid dynamics and predictive control

“…The numerical simulation results were consistent with the experiment. [22][23][24][25] In this article, the mature CFD method is used to obtain the trimaran hydrodynamic coefficients.…”

Heave and Pitch Motions of a Towed Ship in Waves Incorporated with an Asymmetrical Bridle Towline Model

“…Several researchers had investigated on the ship towing system configuration of towline model. The study shows that the asymmetrical bridle towline configuration [3,4] has better course stability compared to single [2] [5,6] and symmetrical bridle towline model [3,[7][8]. These course stability of barge had focused on the sway and yaw motion of barge.…”

“…CFD is a reliable and practical tool to solve maritime problem such as ship towing, seakeeping and analysing the ship resistance. There are researchers such as those in [8,13,21,22], [1,3,23,24] that have been using the CFD since it can capture the hydrodynamic force and non-linear phenomenon during the simulation [1,9]. This paper proposes an analysis on heave and pitch motion of a towed ship in wave using an asymmetrical bridle towline model by using CFD.…”

Prediction of Propeller Performance Using Computational Fluid Dynamics Approach

“…This experimental method is very expensive, time-consuming, and have a complex procedure for various hydrodynamics analysis test configuration. Following the works of [12][13][14][15][16], the numerical methods are adopted to solve and analyze the fluid problem. The computational fluid dynamics (CFD) simulation are the best alternative with several advantages such as allow to simulate using actual and model geometry scale in extreme condition of the fluid flow and the CFD simulation also have a good agreement with experimental data [17][18][19][20].…”